Weft-manipulating and protective means for looms



Oct. 15, 1957 B. B. PURDY 2,809,672

WEFT-MANIPULATING AND PROTECTIVE MEANS FOR LOOMS Filed June 28, 1954 6 Sheets-Sheet 1 INVENTOR B BRucE Brlglg m" 2 I d ATTOQAFEY WEFT-MANIPULATING AND PROTECTIVE MEANS FOR LOOMS Filed vJune 28, 1954 B. B. PURDY Oct. 15, 1957 6 Sheets-Sheet 2 m RH QN IQ Q1 INVENTOR @n v @Q B. PURDY BRUCE a JVM 'TTORNE Y Oct. 15, 1957 B. B. PURDY 2,809,672

WEFT-MANIPULATING AND PROTECTIVE MEANS FOR LOOMS Filed June 28, 1954 6 She'ets-Sheet 4 FIG. 6

INSULATION FIG.8 10o 98%; 107

65 62 4 'INVENTOR {Z BRUCE B. PuRDY WOC Q ATTORNEY B. B. PURDY Oct. 15, 1957 WEFT-MANIPULATING AND ROTECTIVE MEANS FOR LOOMS 6 Sheets-Sheet 5 BACK 7 L LAY LAYFORWARD 15 Filed June 28, 1954 FIG. 9

,/ 320a mmw 0 0 ml x we M L 3 mm SMfi T L 5 W m w -0 @W L fiflfifl T M a w/ HWm m w 7 VY y t F? 5 w w ,i .5 9 o a 1 8 7m 2 7W w m 6 mm P 3 349 2 7 0O 6 8 8mm 66 @(W Q ATTORNEY United States Patent F WEFT-MANIPULATIN G AND PROTECTIVE MEANS FOR LOOMS The present invention relates to looms for weaving wire cloth and other fabrics, and more particularly to weft manipulating means and to loom protective systems cooperating therewith.

An object of the invention is to provide a loom having a protective system which includes electric control elements responsive to abnormal loom operation and which is so arranged as to prevent damage to the loom and the cloth woven thereon in the event of failure of the control elements.

Another object is to provide a loom protective system including cooperating safety switches which are so interconnected as to afiord a mutual supervisory action and indicate failure thereof, and to stop the operation of the loom upon switch failure.

Still another object is to provide a loom protective system of this character in which cooperating safety switches are associated with weft tensioning or stretchofi means for the loom.

A further object is to provide a loom protective system in which cooperating shuttle-controlled safety switches are associated with shuttle boxes of the loom.

A further object is to provide a loom having improved stretch-off means of simple, durable and reliable construction for tensioning and positioning a weft in a Warp shed preparatory to beat-up.

A further object is to provide weft stretch-off means which is mechanically independent of the lay motion of the loom, which will operate smoothly and minimize wear on the moving parts, and which will permit increased weaving speed.

A further object is to provide a weft stretch-off device actuating means therefor forming a unit adapted to be mounted on a loom lay.

A further object is to provide weft stretch-oi means which is controlled by fluid pressure and is readily adjustable to obtain optimum operating conditions.

' A further object is to provide a weft stretch-0E device which is spring-urged in stretch-off direction and in which the spring force can readily be varied to suit different types of weft material.

A still further object is to perfect details of construction generally.

The invention further consists in the several features hereinafter described and claimed.

in the accompanying drawings, illustrating certain embodiments of the invention,

Fig. l is a right-hand side elevation of a wire-weaving loom embodying the invention, the loom lay being shown in its freely suspended position;

Fig. 2 is a similar view of a portion of the loom on an enlarged scale;

Fig. 3 is a schematic sectional loom taken generally on the line 33 of Fig. 1, showing the weft stretching-off operation, the position of the laid weft immediately before stretch-off being indicated by broken lines;

Fig. 4 is a detail front elevation of the led-hand layview of a portion of the 2,809,672 Patented Oct. 15, 1957 carried shuttle box and weft stretch-off assembly, a weftengaging arm of the assembly being shown in retracted position, and parts of a loom frame being shown in section:

Fig. 5 is a detail top plan view of the left-hand laycarried shuttle box and weft stretch-off assembly, the weftengaging arm being shown in various advanced positions in full and broken lines and in retracted position in broken lines, and parts of the loom frame and lay being shown in section;

Fig. 6 is a detail top view of the left-hand stretch-off mechanism with the weft-engaging arm thereof in retracted position, parts being broken away and parts being shown in section;

Fig. 7 is a detail front elevational view of the stretchofi mechanism of Fig. 6, parts being shown in section;

Fig. 8 is a detail bottom plan view of the stretch-off mechanism of Fig. 6;

Fig. 9 is a detail vertical sectional view taken generally on the line 9-9 of Fig. 6;

Fig. 10 is a fragmentary bottom view of the left-hand shuttle box, parts being broken away and parts being shown in section;

Fig. 11 is a detail view of a lay-actuated switch assembly;

Fig. 12 is a detail front elevational view of a modified form of stretch-off controlled safety switch mechanism;

Fig. 13 is a schematic wiring diagram of a loomcontrolling and protective system, and

Fig. 14 is a schematic wiring diagram of a portion of a modified system.

In the drawings, the invention is shown to be embodied in a wire weaving loom which by way of example may be of the general type disclosed in United States Patent 1,790,335 to Weissenborn for Power Loom, issued January 27, 1931. The loom includes spaced side frame members 15 between which are mounted a rotatable warp beam 16, a stationary breast beam 17, and a rotatable cloth roll 18, all as usual. The warp beam carries a supply of warp wires 19- that extend forwardly through reciprocable heddles 20 to form a shed which is opened and closed by the usual shedding motion. Weft wires 21 are laid in the shed by a pith-carrying shuttle 22 movable back and forth between right-hand and left-hand shuttle boxes 23a and 23b, the shuttle boxes being rigidly carried on opposite ends of a swinging lay 24 operated as hereinafter described. The shed converges forwardly to a beat line or fell 25 into which the laid weft is beat up by the lay to form woven cloth 26, the cloth passing about the breast beam and being wound onto the cloth roll. Two heddles are shown but more may be provided. By way of example, three heddles are commonly used in a loom for weaving twill weave wire cloth.

The heddles 20 are connected by chains 27, Fig. 1, to an oscillatory heddle shaft 28 in the usual manner, and the heddle shaft is connected by chains 29 to a pair of treadles 3% which are pivotally mounted at their rear portions on the loom frame. The treadles 3t serve to oscillate the heddle shaft 28 through the chains '29 and are rocked by the usual cam shaft 31, Fig. 3, as in the above United States Patent 1,790,335.

The cam shaft 31 is driven from any suitable source of power, preferably including an electric motor 32 which transmits power to the cam shaft through a combined friction clutch and brake unit 33 and a speed reducer 34. The clutch-brake unit 33 is provided with a shifting lever 35 connected by a link 36 to a lever 37 secured to the rear end of a horizontally disposed rock-shaft 38 journalled on a side frame member of the loom. The forward end of the rock-shaft is provided with an upwardly projecting lever 39 having a forked upper end operatively connected to the usual shipper rod or clutch i 3 pole 4% which extends horizontally at the front of and parallel to the breast beam 17, the opposite ends of the shipper rod being slidably mounted in brackets 41 carried by the side members of the loom frame. By means of the above described connection including the shipper rod 40 and the clutch-brake unit 33, the operator is able to control the transmission of power to the heddle-operating cam shaft 31 or to stop the operation of the cam shaft, and this may be accomplished at any point along the front of the loom.

' The swinging lay 24, here shown to be of the pivotally suspended type, includes the usual horizontally extending lay beam 42 secured to the lower ends of side arms or swords 43, and further includes the usual lay cap 44 between which, and the lay beam, is detachably secured the usual reed 45. The reed comprises parallel steel strips or dents 46 forming between them narrow spaces receiving the warp wires therethrough, the forward edges of the dents being disposed in a plane to form the face of the reed for beating up the weft wires. During its flight between the shuttle boxes, the shuttle is supported on the usual race member 47 pivotally mounted on the lay to underlie the floor of the shed.

The lay is swingable between a back position or dwell and a forward or beat position, and is retracted to its back position by compressed air. As in the above United States Patent 1,790,335 to Weissenborn, the lay retracting means comprises a trunnioned air cylinder 48 in which is movable a piston 49 secured to a rod 50 the forward end of which is pivotally attached to the middle portion of the lay. Upon release of air pressure from the air cylinder, the lay will swing on its forward or beat-up stroke by gravity and with the assistance of the usual coiled tension spring 51 which is connected at its rear end to the loom frame and at its front end to a rock lever 52 operatively connected to the lay by a link or pusher rod 53, the spring being capable of adjustment to regulate the throw of the lay. Admission and exhaust of air with respect to the cylinder 48 are effected by the usual solenoid-controlled valve 54 with a winding 55, the winding being deenergized to charge the air cylinder for effecting retraction of the lay, and being energized to exhaust the air cylinder for permitting fall or advance of the lay on its beat-up strokei The shuttle is thrown through the shed as by means of picker sticks 56 each connected at its lower end to a picker block 57 slidable in the associated shuttle box and engageable with the shuttle. The usual shuttle brake or check 58 is provided at each shuttle box. The picker sticks are pivotally mounted on respective brackets 59 secured to the lay swords and are alternately actuated by respective air cylinders 50 carried on the upper portions of the lay swords. The admission and exhaust of air with respect to the air cylinders 6% is effected by suitable valve means operated either mechanically or electrically. By way of example the valve means for the respective pickerstick cylinders may consist of solenoidoperated three-way valves 61 which are alternately and momentarily energized at the'proper points in the loom cycle to throw the shuttle in opposite directions. As usual, each picker stick is spring-retracted and its throwing travel is limited by a cushion buffer 62, Fig. 4. A generally similar form of picker mechanism is shown in United States Patent 978,248 to Weissenborn, issued December 13, 1910, this patent disclosing mechanically operated valve mechanism for the air cylinders. However, picker mechanisms may be controlled either mechanically or electrically, as is well understood in this art.

The loom is provided with automatic weft stretch-oil? or tensioning means, as hereinafter described, the stretchoif means constituting an improvement over that disclosed in theabove United States Patent 978,248 to Weissenborn. In accordance with one feature of the invention the stretch-off means is so constructed'and arranged as to permit more favorable timing of the operation there-' 2,soo,672

of, to reduce wear, and to allow increased loom speed.

In accordance with another feature of the invention, the weft stretch-off means cooperates as hereinafter described with safety switches forming part of a loom protective system to stop the operation of the loom if the weft wire is absent or improperly laid, the safety switches being so interconnected in the system as to aiford a mutual supervisory action and to stop the operation of the loom upon switch failure.

Each shuttle box has mounted thereon a bracket frame 63 which has a flanged base portion 64 rigidly secured by screws 65 to the front wall of the box near the inner end of the box, and has an upstanding portion 66 with a cantilever arm 67 spaced above the base portion. An upright rock-shaft 58 extends through the base portion and is journalled in a bearing bore 69 formed in the base portion and in a spring-adjusting bearing bushing 7%) detachably and rotatably fitting in a bore 71 formed in the bracket frame arm 67 coaxially of the rock-shaft, the spring-adjusting bushing having a hexagonal top flange 72 resting on the arm and being secured to the arm in angularly adjusted position by a cotter pin 73 passing through a vertical hole 74 in the arm and through any one of circular series of vertical holes 75 in the bushing flange. The rock-shaft is suitably confined against axial shifting, as by snap rings 76 and 77 thereon, the snap.

ring as engaging the underside of the base portion and the snap ring 77 engaging the flat top face of the bushing flange 72.. An apertured arm clamp 78 is pinned to the rock-shaft 6% between the base portion and the bracket frame arm 67 and has a horizontal bore 79 laterally oifset from the axis of the rock-shaft. The outer portion of the clamp has a horizontal slot 8%) extending from the bore 79 to form resilient parallel flanges 31 which are connected by clamping screws 82. A stretch-off arm 83 has an inner end portion slidably fitting in the bore 79 and clamped therein in longitudinally adjusted position by the screws 82. The inner end portion of the stretchoff arm has a fiat 84 at one side laterally engageable by a taper pin 85 in the clamp to prevent angular shifting of the arm on its axis. The stretch-off arm 83 has a downturned outer end rotatably carrying a vertical weftengaging spool 36 of suitable material, such as Micarta, the spool tapering downwardly and having a peripheral flange 87 at its lower end.

The arm-carrying rock-shaft 68 is urged to stretch-off position by a helical torsion spring 88 which surrounds the rock-shaft between the arm clamp 78 and the bushing "7%. The spring 88 is passed over the shaft and through the bore 71 bushing is removed, thus facilitating assembly and permitting selective use of various springs of difierent strength to suit the gage and characteristics of diiierent weft wires. The torsion spring has a downturned lower end 89 engageable in a vertical bore 99 in the arm clamp 78, and has an upturned upper end 91 engageable in a vertical bore 92 in the lower end of the bushing 76. The spring 88 is placed under the desired tension by rotating the bushing 70 which is then locked in angularly adjusted position by the cotter pin 73. V

The stretch-off arm 83 is swingable by the torsion spring 88 from a retracted position shown by full lines in Fig. 4 and in broken lines in Fig. 5 to a variable advanced position such as that shown by full lines in Fig. 5, other normal advanced positions being indicated by broken lines in Fig. 5. In the retracted position of the stretch-off arm, the arm extends above the path of the.

shuttle, as seen in Fig. 4, and the downturned spoolcarrying end of the arm is rearward of the path of the shuttle and beyond the end of a rear shuttle guard plate 93 of the shuttle box, as seen in Fig. 5, so as not to interfere with the flight of the shuttle. The spool is then in a position to swing forwardly into engagement with the weft wire left by the shuttle. a

The stretch-01f devices are mechanically independent of the cantilever arm'while the t of each other and of the lay motion and other loom motions. Each stretch-off arm 83 is urged to retracted position by a small air cylinder 94 which is electrically controlled as hereinafter described. The air cylinder extends horizontally and parallel to the shuttle box at the front thereof, and is mounted on an extension bracket or switch housing 95 which is secured to the bracket frame 63, as by screws 96. A piston 97, Fig. 6, is reciprocable in the air cylinder 94 and is connected to a piston rod 98 to which a head 99 is fastened. A fiat link or connecting rod 166 is pivotally secured at one end to the piston rod head 99, as by a pin 101, and is pivotally secured at its curved or hooked opposite end to the under side of the arm clamp 78, as by a screw 102, Figs. 7 and 9. The power stroke of the piston is suitably limited as by a cushioning washer 103 on the piston rod, and the maximum exhaust stroke of the piston is also suitably limited, as by abutment of the piston with a cushion member 154 in the outer end of the cylinder.

The right-hand and left-hand stretch-off air cylinders 94 have their outer ends connected by flexible hoses 335 to respective alternately operated three-way air valves res, these valves having respective actuating solenoids or windings 167a and 167!) which are controlled as hereinafter described. Each air valve is preferably stationary and is mounted on the adjacent side frame member of the loom, as by an angle bracket 168. An air line 109 supplies compressed air to each valve and is provided with a throttle valve 119 for adjustably controlling the power stroke of the associated air cylinder. An exhaust pipe 111 is mounted on the air valve and is provided with a throttle valve 112 for adjustably controlling the rate of exhaust from the air cylinder, thus controlling the advancing stroke of the associated stretch-ofi arm. In a preferred arrangement, energization of either of the valve windings 197a and 19717 admits compressed air from the valve to the associated air cylinder 94 to move the stretchoff arm 83 to retracted position. Upon deenergization of the valve winding, the air valve returns to exhaust position, permitting the torsion spring 88 to swing the stretched arm to advanced position. The inlet throttle valve 110 regulates the speed of the arm-retracting power stroke of air cylinder piston 97, and the exhaust throttle valve 112 regulates the speed of the exhaust stroke of the piston, thus affording a cushioning action and insuring smooth operation.

During the flight of the shuttle through the shed, the weft wire 21 is paid out from the shuttle pirn 113, and after the shuttle is boxed the weft wire is pinched or held near the boxed shuttle during the stretch-0E operation. For this purpose each stretch-off device has associated therewith a weft wire clamp 114.

Each wire clamp 114 includes a reciprocable vertical stem 115' slidably mounted in a flat-topped bushing 116 pressed flush into the base portion of the bracket frame 63 near the front wall of the shuttle box and adjacent the entrance of the box, the stem extending in parallel relation to the rock-shaft 68. A flanged sleeve 117 is pressed onto the upper end of the stem and a vulcanized fiber washer 113 with a convexly rounded marginal bottom portion is pressed onto the stem into abutment with the lower end of the sleeve. The fiber washer 118 is adapted to clamp a weft wire against the bushing 116, and the clamp is urged downwardly by an axially aligned overlying helical spring 119 which is placed under adjustable compression by a flanged locator stem 12f) screwthreaded into the bracket frame arm 67, the locator stem being locked in adjusted position by a nut 121.

In the retracted position of the stretch-off arm, the wire clamp 114 is lifted out of clamping position by cam means actuated by the rock-shaft 68. A lifter lever or bell-crank 122 is pivotally secured by a horizontal pin 123 to a pair of spaced vertical ears 124 formed on the under side of the bracket frame 63, the lever being confined between the ears and extending in the common vertical plane of the rock-shaft 63 and wire clamp stem One arm of the lever 122-extends in a generally horizontal direction and is engageable withthe rounded lower end of the wire clamp stem 115, and the other arm of the lever extends downwardly and carries at its lower end a radial pm 125 rotatably supporting a rounded roller 126. The roller 126 bears on the periphery of a disk cam 127 secured to the lower end of the rock-shaft 68,

as by a set screw 128 and nut 129. The cam 127 is an-.

gularly adjustable on therock-shaft and is made symmetrical so that it can'bereversed when worn.

The weft stretch-off devices are also used as part of a loom-controlling system responsive to weft failure, as hereinafter described. For this purpose, the right-hand and left-hand weft stretch-off devices have associated therewith respective safety switches 130a and 1301) each of which is here shown to be of a single-pole doublethrow type. As best seen in Pig. 7, showing the lefthand stretch-ofi device and associated safety switch 130b, this switch is mounted on the extension bracket 95 and is provided with an actuating arm 131 the roller 132 of which rides in a cam groove 133 formed in a block 134 carried on the piston rod head 99. With normal stretchoff each of the safety switches 130a and 13% will be positively actuated to a first closed position when the associated stretch-off arm 83 is in retracted position, and will be positively actuated to a second closed position when the stretch-0d arm is in a normal range of advanced positions, the switch being in its second position if the weft wire is properly laid so as to permit continued operation of the loom, as hereinafter described. The switch opens from its first closed position when the stretchoff arm swings forwardly from its retracted position and then closes to its second position when the stretch-ofi arm reaches its normal range of advanced positions. if the weft wire is absent as by reason of an empty shuttle pirn, or if the weft wire is too short or is broken, or is excessively slack as by reason of a defective Weft wire clamp, the stretch-ofi arm will swing forwardly beyond its normalrange of movement, thereby causing the switch 13% (or 139a) to open or to reclose in its first position. If the weft wire is laid in such manner as to have inadequate slack, such as by reason of an improperly operating pirn, the stretch-oft arm will swing forwardly an insufficient distance to close the switch 13% (or 13%) to its second position, whereupon, in either case, through suitable control means hereinafter described, the loom will be stopped. Referring to Fig. 5, the switch 13011 will be actuated 'to its second closed position whenever the stretch-off arm is in the range between the two forward arm positions shown by broken lines.

The modification shown in Fig. 12 includes a stretchofi safety switch 33012 of the micro style mounted on the extension bracket '75. The switch is of the single-pole double-throw snap type spring-biased to its first closed position and carries a roller arm 331 cooperating with a cam block 334 secured to the 1% to actuate the switch to its second closed position. The switch arrangement of Fig. 12 is otherwise the same as that of Fig. 7 and has the same operating conditions, except that by reason of the snap action the switch will not remain in an open position.

The left-hand shuttle box 23b is provided with a pair of shuttle-operated control switches 13512 and Bob, Figs. 3, 4, 5, and 10, and the right-hand shuttle box 23a is pro vided with a pair of similar switches 135a and 136a, Fig. 3. The several switches are each operable to first and second positions, and are included in a loom control system as hereinafter described. By way of example, the the switches proper are here shown to be of the micro switch plunger type, as best seen in Fig. 10, each switch being internally spring-biased to its second position when the shuttle is in the box. The two switches for each shuttle box are carried on a mounting plate 137 which is adjustably secured to the bottom of the shuttle box by screws 138. e The switches are actuated by respective bell-crank levers 139 and 140 swingably carried on parallel pivots 141 on the mounting plate, one arm of each lever engaging the switch plunger of the associated switch, and the free ends of the two plunger-engaging arms being connected by a coiled spring 142 to urge the two switches to their first positions. The other arms of the two bellcrank levers engage respective headed fiber pins or buttons 14-3 and 144 which extend transversely through the rear wall of the shuttle box in slidable relation thereto. The slidable fiber pins are displaced outwardly by the shuttle when it enters the box to permit the two switches to assume their second positions. The fiber pin or button 14.3fm each of the switches 135a and 13512 is so located as to be displaced by the shuttle as it enters the box, and the fiber pin or button 144 for each of the switches 135a and 1156b is so located as to be displaced by the shuttle when it is fully boxed. The two switches associated with each shuttle box are thus actuated in succession to their second positions when the shuttle is boxed, and are successively actuated in reverse order to their first positions when the shuttle starts on its flight. Each of the switches 135a and 135]) is of the snap type and is in its first position, for example a closed position, when the shuttle is out of the associated box, and is in its second position, for example an open position, when the shuttle is in the box. Each of the switches 136a and 2361'; is of the single-pole double-throw snap type and makes contact in both of its first and second positions, each switch being in its first closed position when the shuttle is out of the box and being in its second closed position when the shuttle is in the box. The several shuttle box switches are connected in control circuits as hereinafter described, the switches 135a and. 1351) being so interconnected as to afford a mutual supervisory action for protection against switch failure. 7

The control system of the loom includes a rotary timer cam switch mechanism 145, which schedules the sequence of events for the operation of the loom. The switch mechanism includes a cam shaft 146 suitably driven from the shed-changing drive shaft or cam shaft 31, as by a chain 147, to time the schedule with the shed changes. In the present instance the cam shaft 146 of the switch mechanism is driven at the same speed as the shaft 31. The cam shaft 146 carries thereon a series of cams 148, T52, 154, 156, and 158 for operating respective micro switches 149, 151, 153, 155, 157, and 159 during the rotation of the cam shaft. The several. cam-operated switches are connected in the system as. hereinafter described.

The loom control system further includes a switch 166 which is controlled by the lay or its associated linkage. The switch 166 is here shown to be mounted on one of the side frame members of the loom, as best seen in Fig. 11, and is actuated by a cam 161 adjustably mountedon a bracket 162 secured to the adjacent lay sword. The switch 169, which may be of an overtravel lever type, is closed for most of the loom cycle and is open for an interval during the forward stroke of the lay to test for a properly laid weft wire, as hereinafter described. The adjustable cam 161 engages the roller-carryingrccl: lever 163 of the switch 165). On the retracting stroke of the lay the cam 161 swings the rock lever 163 rearwardly without opening the switch, and on the for ward stroke of the lay the cam swings the rock lever forwardly to open the switch shortly after the lay starts to fall, the switch reclosing shortly before the time of beat. As seen in Fig. 13, the switch 164 may include a pair of series-connected switch sections so that if one section should fail in closed position the other switch section will remain operative. V

The clutch-brake operating lever 3?, which is swung by the shipper rod 39, actuates a lever-type switch mechanism or control station of conventional construction comprising a switch 1&4. In the off positionof the shipper rod, the switch 164 is open, and in the on position of the shipper rod the switch is closed. The switch 164 is used to control various loom circuits as hereinafter described. 7

The .loom control system includes control lines or buses 165 and 166 which supply'alternating current at a suitable voltage, such as volts, to some of thecontrol circuits. A step-down transformer 157 is connected across the buses and 166 and supplies current u is connected to control lines or buses 16? and 170 which furnish direct current at low voltage, such as 12 volts, to other control circuits.

The clutch-brake unit 33 is under the control of a 'l or winding 171, which by way of example may be a up winding associated with the link 36 or other part of the clutch-operating linkage, the link being of. a releasable or collapsible type. In the case of a magnetic clutch, the winding 1'71 may constitute the energizing winding of clutch. The clutch control winding 171 is supplied with current from the control buses or lines 1&5 and 166 and is controlled by the shipper rod switch PM and by a loom stop relay 172 having switches 1'73 and 174 and winding 175, the reiay switch 173 being connected in series with the clutch control winding. C ne terminal of the shipper rod switch ld i is connected to the control bus 1&5 and the other terminal is connected by a conductor 75 to one terminal of the relay switch 173. The other terminal of the relay switch is connected to one terminal of the clutch control winding 17 1, and the other terminal of the clutch control winding is connected to the control bus 166, thus completing the circut through the clutch control winding. 7 Whenever the winding 175 of the loom stop relay 172 is energized, as hereinafter described, the relay switches 173 and 174 are closed, and if the shipper rod switch 164 is also closed a circuit is established through the clutch control winding 171 from the control buses 165 and 166. The relay switch 174 is connected in series with the lay retractor winding 55, which is controlled as hereinafter described.

The coil or winding 55 for the lay retractor valve is energized from the control lines or buses 165 and 166 through selectively active circuits including respective conductors 177 and 178. Whenever the winding 55 is energized the lay will fall or advance, and whenever the circuit through this winding is interrupted the lay will return to its back position. The winding 55' has one terminal connected to the control bus 165, and the other terminal is connected to a conductor 179 which includes in series the switch 174 of the loom stop relay and one or more normally closed, lay-control, push-button switches 189 which are mounted on the loom frame or on the lay, or on both the loom frame and lay. A selector switch 181 of the single-pole double-throw type has its common terminal connected to the control bus 65. A second terminal of the selector switch, labeled Loom off, is connected by the conductor 17% to the junction of the conductors 177 and 179. A third terminal of the selector switch, labeled Loom on is connected to stretcholf control circuits as hereinafter described. The laycontrol push-button switches 181? may be operated for inching or manually controlling lay operation. During this operation the selector switch 131 is in Loom off position and the shipper rod switch 164 is in off position.

The conductor 177 of the other of the selectively active control circuits for the lay retractor valve winding 55 includes the timer cam switch 14?. The cam switch 149 is operated twice in each revolution by the twolobed timer cam 143 and controls the energization of the lay retractor valve winding 55 during normal operation of the loom. The timer-controlled circuit for the lay retractor valve includes in series the shipper switch 164, a pair of normally open, parallel-connected relay switches bridge-type rectifier 168, the output of which 182 and 183 of respective shuttle position relays 184 and 185'responsive to shuttle homing, and'the switch 174 of the loom'stop relay 172, the latter relay being energized as hereinafter described. The relay switches 182 and 183 of the shuttle position relays 184 and 185 are alternately closed during timer-controlled operation of the loom, 'as hereinafter described, to complete the circuit through the'tirner cam switch 149. The loom stop or safety relay 172' is automatically deenergized under abnormal conditions, as hereinafter described.

The timer cam switches 151 and 153 are reset switches for the right-hand and lefthand electro-pneumatic stretchoff devices. The windings 107a and 107b for these devices each have one terminal connected to the control bus 166, and the other terminals of the windings are connected'by respective conductors 186 and 187 to termirials of the respective cam switches 151 and 153. The other terminals of these switches are connected by a conductor 138 to the Loom on terminal of .the selector switch 181. The reset timer switches 151 and 153 are connected in parallel with the respective shuttle box switches 135a and 135b which are opened by boxing of the .shuttle. Each reset timer .switch isset to open shortly before the shuttle is due to arrive in the corresponding shuttle box so that arrival of the shuttle will open the corresponding shuttle box switch 135a or 135!) and thusinterrupt the circuit through the valve winding of the corresponding stretch-01f device, whereupon stretchoff of the weft will occur. Each reset timer switch recloses at about the time of beat so as to .reenergize the corresponding stretch-oft" valve winding and thus effect retraction of the associated stretchaoif arm before the next throw of the shuttle.

vActuation of the selector switch 181 to Loom ofi position will deenergize the weftstretch-off valve windings and thus permit both stretch-off arms to advance. However, the stretch-off arms may be retracted by manually operable resetting means comprising a shunting circuit including a double-pole push-button switch 189 which if desired may be of the locking type. A conductor 190 connects the control bus 165 with the common terminal of the pushfbutton reset switch 189, and conductors 191 and 192 connect theother terminals of the push-button switch with the conductors 186 and 187. If the push-button switch 139 is closed while the stretchoff arms are retracted, these arms will remain in their retracted position.

The winding 175 of the loom stop relay 172 is energized from the control buses 165 and 166 through a conductor 193 which includes a switch 194 of a low voltage auxiliary relay 195 controlled as hereinafter described. The coil of the auxiliaryrelay has one terminal connected to the low voltage bus 170 and the other terminal is connected to the other bus 169 through a holding switch 196 and through parallel circuit paths comprising conductors 197, .198, and 199 each including switchesas hereinafter described. The relay .195 has its normally open holding switch shunted by a reset push-button switch 200 by which the circuit through the relay winding can be reclosed when required. The common terminals of the two alternately operable stretch-off safety switches 130a and 13012 are connected by a conductor 201, and the first-position terminals of these switches are connected to the control bus 169. The second-position terminal of the switch 1300 is connected to the conductor 197, and the second-position terminal of the switch 13Gb is connected to the conductor 198. The conductor 197 further includes a relay switch 202 forming part of the shuttlefcon rolled relay 184, and also the rotary timer switch 155. The conductor 198 further includes a relay switch 203 forming part of the shuttle-controlled relay 185, and also the rotary timer switch 157. While the relay switches 202 and 203 and the timer switches 155 and 157 afford additional circuit protection they are not always necessary and may either be omitted or shunted out of circuit by a conductor 204 and a switch 205. The conductor 199 includes the lay switch 160 and the series-connected timer switch 159. As previously noted, the lay switch 160 is open for an interval during the'fall or advance of the lay to test for an improperly laid or absent weft. The timer switch 159 is set to open soon after the time scheduled for stretch-off and opens either while the lay is at its back position or shortly after the lay starts to fall. This timer switch recloses during the open period of the lay switch 160.

The open period of the timer switch 159 can usually be somewhat shorter than the open period of the lay switch. The timer switch 159 serves to open the circuit through the conductor 199 if the lay switch 160 fails'to open during the fall of the lay, or if the lay does not fall.

The common terminals of the shuttle-operated switches 136a and 1361; are connected by a conductor 206, and the first terminals of these switches are connected to the low voltage bus 169. The second terminals of the switches 136a and 1156b are connected by respective conductors 207 and 208 to terminals of the respective relay windings 184 and 185, and the'other terminals of these relay windings are connected to the low voltage bus 170.

In the modified form of control circuit shown in Fig. 14, the stretch-off safety switches a and 1301) have a different form of series connection, and the relay switches 202 and 203 and timer switches and 157 of Fig. 13 are omitted. If the relay switches 202 and 203 and the timer switches 155 and 157 are to be provided, they are inserted at the points A and B of Fig. 14. The common terminal of the safety switch 13hr: is connected to the low voltage bus 169. The first-position terminal of the safety switch 130a is connected by a conductor 209 to the second-position terminal of the safety switch 13%, and the second-position terminal of the safety switch 130a is connected by a conductor 210 to the first-position terminal of the safety switch 1313b. The common terminal of the safety switch 130!) is connected by a conductor 211 to a terminal of the holding switch 196 of the auxiliary relay 19.5, and the other terminal of the holding switch is connected to the low voltage bus 170. The rest of the control circuit of Fig. 14 is like that of Fig. 13.

When the loom is in normal operation, weft is laid in the warp shed by cyclic passage of the shuttle back and forth between the shuttle boxes. The loom stop relay 172 must be energized to close the associated switches 173 and 174-. Energization of the relay 172 is effected by energizing the auxiliary relay 195 by the reset push-button switch 200. The shuttle must-be fully boxed, energizing the relay 184 or the relay 185 to close the associated relay contacts 182 or 183. The shuttle pirn must be full or at least have suflicient wire to complete a weft shot. The motor must be running, and the shipper rod must be in on position, so as to operate the shedding motion and cam switch mechanisms and to complete a supply circuit for the lay retractor valve winding and the clutch control winding. The selector switch 181 must be in Loom on position so as to permit operation of the stretch-off devices.

Assuming the shuttle 22 to be thrown from the righthand shuttle box 23a, the shuttle flies through the fully open shed toward the left-hand shuttle box 23b while the lay 24 is at the latter part of its back stroke or has reached its back position,- and lays a weft 21 in the shed. Upon arrival of the shuttle in the left-hand shuttle box it operates in quick succession the shuttle box switches 135b and 136b, the former being opened and the latter being shifted from its first closed positionto its second closed position. The opening of the shuttle box switch 135k deenergizes the left-hand stretch-off valve winding 107b, since the timer switch 153 shunting this shuttle box switch has already opened shortly before arrival of the shuttle. The deenergization of the stretch-elf valve winding 107i; effects eichaustof the air cylinder 94 under control of the throttle valve 112, causing a smooth spring'urged release of the left-hand stretch-01f arm to its forward position. This release of the left-hand stretch-off arm is immediate and occurs while thelay is at its back position. The right-hand stretch-off arm remains in retracted position until the shuttle returns to the right-hand shuttle box.

As seen in Fig. 3, the newly inserted weft extends in a diagonal position indicated by broken lines and while the shed is fully open and the lay is in its back position the left-hand stretch-off arm 83 shifts the weft to a position close to and substantially parallel to the fell or face of the work and in a substantially straight condition, the tensioning of the weft removing curls and waves therefrom. During the initial part of the forward swing of the stretch-off arm the high part of cam 127 on the rockshaft 63 rides off the roller 126 on the bell-crank lever 122, thus permitting the spring 119 to move the fiber clamping washer 118 downwardly for clamping the weft wire between the washer and the top face of the bushing 116 and thereby prevent further pay-out of weft wire from the shuttle pirn during the stretch-oif operation. The rounded or tapered edge of the clamping washer 118 insures entry of the weft Wire under the clamping washer.

With normal stretch-off the left-hand stretch-off safety switch 13017 is shifted from its first closed position to its second closed position, thus placing the two switches 13012 and 13% in series by way of the conductor 21. 1 and establishing a circuit path in parallel to the circuit path containing the lay-actuated switch 16%) and the timer switch 159 for a later weft test. The circuit path through the stretch-off safety switches extends from the low voltage control bus 169, the switch 130a (then in its first closed position), the conductor 201, the switch 13012 (then in its second closed position), the conductor 198, the then closed relay switch 203, the then closed timer switch 157,

' the holding switch 196, and the winding of the auxiliary relay 195 to the low voltage control bus 170, thus maintaining the energization of the auxiliary relay to insure continued loom operationv As soon as the shuttle is fully boxed, the left-hand shuttle box switch 13617 is shifted from its first closed position to its second closed position, thus placing the two switches 136a and 1156b in series by way of the conductor 296, and energizing the shuttle homing relay 185 from the low voltage buses 169 and 179. Energization of the relay 185 closes the associated switch 183 in the circuit of the lay-retracting valve winding 55 and also closes the associated switch 203 in the circuit path 198 including the left-hand stretch-off safety switch 13Gb. The timer cam switch 157 in this circuit path closes shortly before stretch-off and remains closed until shortly after beat-up.

Soon after boxing of the shuttle in the left-hand shuttle box the timer cam switch 149 closes to complete the circuit through the winding 55 of the lay retractor valve, releasing the compressed air from the air cylinder 48 and permitting fall of the lay by gravity and spring action on its beat-up or forward stroke. During the initial part of the fall of the lay, the stretch-off arm 183 brings the laid Weft closer to the fell, if the stretch-elf is not completed while the lay is in its back position. After the lay fails a short distance, lay-actuated switch 169 opens to test for a properly laid weft wire, as hereinafter described, the latter switch closing before the time of heatup. The timer switch 159 is also open for a time during this interval.

At about the time of beat-up, timer switch 153 recloses, energizing the winding 1137b of the left-hand stretch-off valve to reset the left-hand stretch-off arm to retracted position, the switch 153 remaining closed until just before the shuttle again reenters the left-hand box. The retraction of the left-hand stretch-off arm causes the lefthand safety switch 139b'to return to its first closed position, thus opening the circuit path through the conductor 198. However, before this switch operation occurs the circuit path through the lay switch 160 and conductor 12 a '199 has been restored, so that the auxiliary relay 195 remains energized to permit continued loom operation. The shed changes shortly after the weft is beat up and in someinstances may start to close shortly before beatup.

At about the time of beat-up, the timer switch 149 opens the lay retractor valve circuit, thus admitting compressed air to the air cylinder'48 to return the lay to its back position. The shuttle is then thrown through the shed to the ri ht-hand shuttle box, and a corresponding sequence of events takes place. The right-hand shuttle box switches a and 136a are actuated in quick succession, the switch 135a being opened to effect operation of the right-hand stretch-off device (controlled by the valve winding 167a), and the switch 136a being shifted from its first closed position to its second closed position to energize the relay 184 so as to close relay switch 182 in the lay retractor valve circuit and relay switch 202 in the Sil'fiiCihOfi safety circuit. During stretch-01f the righthand stretch-off safety switch 130a is shifted from its first closed position to its second closed position, thus establishing one of the circuit paths through the winding of the auxiliary relay 195. The timer switch 149 closes to effect fall of the lay on its beat-up stroke and reopens at about the time of beat-up to effect retraction of the lay. During fall of the lay, the lay-actuated switch opens to test for a properly laid weft wire. t about the time of heatup timer switch 153 recloses to effect return of the righthand stretch-off arm to retracted position. During the latter part of the return travel of the lay, or after the lay has reached its back position, the shuttle is thrown through the shed to the left-hand shuttle box, and the cycle of operation is repeated.

if during the operation of the loom either of the stretchoif safety switches 130a and 13Gb fails to remain in or reach its second closed position after advance of the corresponding stretch-off arm, indicating absence of a weft or an improperly laid weft, the circuit path through these series-connected switches will be open, so that the timer switch 159 or the lay-actuated switch 160 will open the circuit through the winding of the auxiliary relay 195, thus opening the holding switch 196 and the relay switch 194. The opening of the switch 194 deenergizes the loom stop relay 172, thus opening the associated relay switch 174 to effect immediate retraction of the lay, and opening the associated relay switch 173 to deenergize the clutch control winding 171, thus bringing the loom to a stop. If the lay-actuated switch 160 should fail to open, or if the lay should fail to fall, the weft-testing circuit will be interrupted at the timer switch 159. If either of the stretchoff safety switches 130a and 1301) should fail in either of its closed positions, or in an open position, regardless of weft condition, the auxiliary relay 195 will be deenergized and stop the loom. If either safety switch should fail in its second closed position, the loom will operate for an additional shuttle throw, and the other safety switch will then be actuated out of its first closed position and interrupt the associated circuit path, so that opening of lay-actuated switch 160, or opening of the timer switch 159, will stop the loom.

If the shuttle should fail to reach fully boxed position in either box, or should rebound from boxed position, the circuit through the shuttle box switches 136a and 136]; will not be completed, and therefore neither of relays 184 and 185 will be energized, preventing fall of the lay since neither of the relay switches 182 and 133 will be closed, and preventing completion of the circuit through the stretch-off safety switches since neither of the relay switches 262 and 293 will be closed. The subsequent open ng of the timer switch 159 will then stop the loom. Loom stoppage will also occur if either of the shuttle box switches 136a and 136b should fail in either closed or open position.

If the shuttle should fail to reach either shuttle box the associated shuttle box switch 135a or 135b will not be actuated and consequently the associated stretch-E arm will not be advanced. The circuit through the stretch-off safety switches 1343a and 13Gb will therefore remain open, and subsequent opening of the timer switch 159 will deenergize the auxiliary relay 195, thus stopping the loom. If the shuttle is too late, loom stoppage will occur in like manner, since the timer switch 159 is set to open soon after the time scheduled for'stretch-off.

Upon stoppage of the loom the shipper rod is moved by the operator to o position, and suitable corrections or adjustments are made. The auxiliary relay 195 is then reenergi ed by momentarily closing the reset push-button switch 2%, thereby reenergizing the loom stop relay 172, and permitting restarting of the loom.

I claim:

1. In a loom having driving means and further having a lay and means for inserting and tensioning a weft in a warp shed, electric control circuit means for said driving means including first and second circuit paths arranged in parallel and cooperating to maintain circuit continuity for permitting continued operation of the loom, circuit closer means for establishing said first circuit path, said circuit closer means comprising a pair of alternately operable switches connected in series in said first circuit path and each having first and second closed positions, said switches being normally urged to their first closed positions, said first circuit path being established when either of said switches is in its first closed position and the other switch is in its second closed position, means responsive to the presence of a normally laid and tensioned weft for alternately actuating said switches to their second closed positions to thereby establish said first circuit path, and cyclically operating circuit closer means for interrupting said second circuit path during the period in'which the forward stroke of the lay normally occurs, whereby it said first circrn't path is open said control circuit means will be interrupted to stop the operation of the loom.

2. in a loom having driving means and further having a lay and means for inserting a weft in a warp shed, means including a pair of alternately effective stretch-off mechanisms at opposite sides of the loom for positioning and tensioning the inserted weft, electric control circuit means for said driving means including first and second circuit paths arranged in parallel and cooperating to maintain circuit continuity to permit continued operation of the loom, circuit closers associated with the respective stretch-oft mechanisms and responsive to the presence of a normally laid and tensioned weft for establishing said first circuit path, said circuit closers being alternately operable and each having first and second closed positions, each circuit closer being actuated to its second closed position when the weft is normally laid and tensioned, said circuit closers being connected in series in said first circuit path, said first circuit path being established when either of said circuit closers is in its first closed position and the other circuit closer is in its second closed position, and cyclically operating circuit closer means for interrupting said second circuit path during the period in which the forward stroke of the lay normally occurs, whereby if said first circuit path is open said control circuit means will be interrupted to stop the operation of the loom.

3. In a loom having driving means and further having a lay and means for inserting a weft in a warp shed, means for positioning and tensioning the inserted weft and including a pair of alternately efiective stretch-off mechanisms at opposite sides of the loom, electric control circuit means for said driving means including first and second circuit paths arranged in parallel and cooperating to maintain circuit continuity to permit continued operation of the loom, alternately operable circuit closers associated with the respective stretch-0E mechanisms and actuated to closed position in response to the presence of a normally laid and tensioned weft, said circuit closers being connected in series in said first circuit path, a second pair of alternately operable circuit closers operable synchro nously with the loom and connected in said first circuit path in series with said respective first-named circuit closers, each of said second-named circuit closers being closed during the normal closure period of the associated first-named circuit closer in series therewith, and'cyclically operating circuit closer means in said second circuit path for interrupting said second circuit path during the period in which the forward stroke of the lay normally occurs, whereby if both of said first and second circuit paths are simultaneously open said control circuit means will be interrupted to stop the operation of the loom.

4. in a loom having driving means and further having a lay and a pair of alternately efiective weft stretch-0E mechanisms, a control circuit for said driving means including a pair of first and second parallel circuit paths, switches associated with said respective'stretch-ofi mechanisms and each operable to alternative first and second closed positions, each switch being actuated to its second closed position by the associated stretch-off mechanism when the weft is normally laid and is tensioned by said mechanism and being at other times in said first closed position, said switches being connected in series in said first circuit path, a cyclically operating switch in said second circuit path closed during most of the loom cycle to maintain circuit continuity in said control circuit but open after a stretch-off operation and during the period in which the advance of the lay normally occurs to interrupt said second circuit path, whereby to stop the loom if the circuit through said first circuit path is open by failure of either of said stretch-off switches to be actuated to its second closed position or by accidental failure of the other of said stretch-01f switches to return from its second closed position to its first closed position after a stretch-ofi operation.

5. In a loom having driving means and further having a lay and means for inserting and tensioning a weft in a warp shed, electric control circuit means for said driving means including first and second circuit paths'arranged in parallel and cooperating to maintain circuit continuity for permitting continued operation of the loom, circuit closer means for establishing said first circuit path, said circuit closer means comprising a pairof alternately operable switches connected in series in said first circuit path and each having first and second closed positions, said switches being normally urged to their first closed positions, said first circuit path being established when either of said switches is in its first closed position and the other switch is in its second closed position, means responsive to the presence of a normally laid and tensioned weft for alternately actuating said switches to their second closed positions to thereby establish said first circuit path, and cyclically operating circuit closer means for interrupting said second circuit path during the period in which the forward stroke of the lay normally occurs, whereby if said first circuit path is open said con trol circuit means will be interrupted to stop the operation of the loom, said last-named circuit closer means including a lay-controlled switch and a timer switch connected in series therewith.

6. In a loom having driving means and further having a lay and means for inserting and tensioning a weft in a warp shed, electric control circuit means for said driving means including first and second circuit paths arranged in parallel and cooperating to maintain circuit continuity for permitting continued operation of the loom, circuit closer means for establishing said first circuit path, said circuit closer means comprising a pair of alternately operable switches connected in series in said first circuit path and each having first and second closed positions, said switches being normally urged to their first closed positions, said first circuit path being established when either of said switches is in its first closed position and the other switch is in its second closed po sition, means responsive to the presence of a normally laid and tensioned weft for alternately actuating said switches to their second closed positions to thereby establish said first circuit path, and cyclicallyoperating circuit closer means for interrupting said second circuit path during the period in which the forward stroke of the lay normally occurs, whereby if said first circuit path is open said control circuit means will be interrupted to stop the operation of the loom, said last-named circuit closer means including a lay-controlled switch and a timer switch connected in series therewith, said timer switch having an open interval which is shorter than the open interval of said lay-controlled switch.

7. In a loom having a shuttle movable back and forth between shuttle boxes, electric circuit means for controlling loom operation including a pair of alternately operable switches responsive to shuttle boxing and each having first and second closed positions, said switches beingnormally urged to their first closed positions and being alternately operable to their second closed positions, said switches being connected in series in said circuit means and establishing circuit continuity therein when either of sad switches is in its first position and the other switch is in its second position, and means responsive to boxing of the shuttle for alternately operating said switches to their second closed positions.

8. In a loom having a lay andra shuttle movable back and forth between shuttle boxes, electric circuit means responsive to shuttle boxing for controlling the fall of the lay and including a pair of alternately operable shuttlecontrolled switches each having first and second closed positions, said switches being normally urged to their first closed positions'and being alternately operable to their second closed positions, said switches being connected in series in said circuit means and establishing circuit continuity therein when either of said switches is in its first closed position and the otherswitch is in its second closed position, and means responsive to boxing of the shuttle for alternately operating said switches to their second closed positions.

9. In a loom having a lay with shuttle boxes and having a shuttle movable back and forth between the shuttle boxes to lay a weft in a warp shed, alternately actuated movably mounted members adjacent to said respective boxes and engageable with the laid weft to tension the weft, resilient means for moving said members in wefttensioning direction, selectively operable power-actuated means for said respective members carried by said lay for alternately moving said members in reverse direction against the pressure of said resilient means to a position out of the path of the shuttle, and control means responsive to the boxing of the shuttle in each shuttle box for deenergizi-ng the associated power-actuated means and releasing the corresponding weft-tensioning member on its weft-tensioning movement,

10. In a loom having a lay with shuttle boxes and having a shuttle movable back and forth between the shuttle boxes to lay a weft in the warp shed, movably mounted members adjacent to said respective shuttle boxes and engageable with the laid weft to tension the weft, resilient means for moving said members in wettensioning direction, fluid pressure actuating means for each of said members for moving said members in reverse direction against the pressure of said resilient means to a position out of the path of the shuttle, and control means responsive to the boxing of the shuttle in each shuttle box for deenergizing the associated fluid pressure means and releasing the corresponding weft-tensioning member on its weft-tensioning movement.

11. In a loom having a lay with shuttle boxes and having a shuttle movable back and forth between the shuttle boxes to lay a weft in the warp shed, movably mounted members adjacent to said respective shuttle boxes and engageable with the laid weft to tension the weft, resilient means for moving said members in wefttensioning direction, fluid pressure actuating means for each of said members for moving said members in reverse direction against the pressure of said resilient means to a position out of the path of the shuttle, and electric circuit means for alternately controlling the fluid pressure actuating means for said members.

7 12. In a loom having a lay with shuttle boxes and having a shuttle movable back and forth between the shuttle boxes to lay a weft in the warp shed, a swi-ngably mounted arm adjacent to each shuttle box and engageable with thelaid weft to tension the weft, resilient means for moving each arm in weft-tensioning direction, an air cylinder operatively connected with each arm for retracting said arm, and control means responsive to the boxing of the shuttle in each shuttle box for deenergizing the associated air cylinder and releasing the corresponding wefttensioning arm on its weft-tensioning movement.

13. In a loom havinga lay with shuttle boxes and having a shuttle movable back and forth between the shuttle boxes to lay a weft in the warp shed, a swingably mounted arm adjacent to each shuttle box and engageable with the laid weft to tension the weft, resilient means for moving each arm in weft-tensioning direction, an air cylinder operatively connected with each arm for retracting said arm, an electromagnetic valve controlling each air cylinder and shiftable to air-admitting and air-exhausting positions, and circuit means operatively connected to each of said electromagnetic valves and responsive to boxing of the shuttle in each shuttle box for actuating the associated electromagnetic valve to its air-exhausting position to release the associated arm on its weft-tensioning movement.

14. In a loom having a lay with shuttle bOXes and having a shuttle movable back and forth between the shuttle boxes to lay a weft in the warp shed, supports carried by the lay adjacent to opposite ends thereof, an arm swingably mounted on each support and transversely engageable with the laid weft to tension the Weft, resilient means for swinging each arm in weft-tensioning direction, an air cylinder carried by each support and operatively connected with the associated arm for retracting said arm, and control means responsive to the boxing of the shuttle in each shuttle box for deenergizing the associated air cylinder and releasing the associated arm on its weft-tensioning movement.

15. In a loom having a 'lay with shuttle boxes and having a shuttle movable back and forth between the shuttle boxes to lay a weft in a warp shed, a pair of reciprocably mounted members adjacent to opposite ends of said lay and alternately engageable with the laid weft to tension the weft, each member being shiftable in a range of movernent between a retracted position and an advanced position, means for shifting each member in opposite directions, each member when shifted in weft-tensioning direction being in an intermediate portion of said range of movement under conditions of normal weft tension, and

loom-controlling circuit-closers each movable to first and second closed positions and operatively connected with said respective members to be actuated therewith to said first and second closed positions, each circuit-closer being in said first closed position when the associated member is in retracted position and being in said second closed position when said member is inthe intermediate portion of its range of movement. 7 p

16. In a loom having a lay and weft-inserting means, a pair of alternately actuated weft-tensioning members each movable on advancing and retracting strokes, an air cylinder o eratively associated with each weft-tensioning member, valve means controlling each air cylinder, and air-restricting means for regulating the rate of travel of said weft-tensioning members. 17. In a loomhaving a lay and weft-inserting means, a pair of alternately, actuated weft-tensioning members each movable on advancing and retracting strokes, and

actuating means for each member including a fluid pressure device for moving said member on one of its strokes.

18. In a loom having a lay and weft-inserting means, a support, a rock-shaft rotatably carried by said support and having a weft-engaging arm, said rock-shaft being angularly shiftable from a retracted position to an advanced position for tensioning the weft, means for swinging said rock-shaft, a reciprocable weft clamp slidable in said support in generally parallel relation to said rockshaft, a cam on said rock-shaft, and a rocker member pivotally carried on said support in operative relation to said cam and weft clamp for controlling said weft clamp, said rocker member including a portion in pushing relation to said weft clamp and movable in a direction extending generally axially of said weft clamp.

19. In a loom having a lay and Weft-inserting means, a support, a rock-shaft rotatably carried by said support and having a weft-engaging arm, said rock-shaft being angularly shiftable from a retracted position to an advanced position for tensioning the inserted weft, a bushing rotatively adjustable in said support and forming a bearing for said rock-shaft, a coiled torsion spring surrounding said rock-shaft and having one end engaging said bushing and the other end acting on said rock-shaft to swing said rock-shaft in Weft-tensioning direction, said bushing being angularly displaceable to vary the torsion of said spring, means for retaining said bushing in rotatively adjusted position, and means for swinging said rockshaft to retracted position against the action of said spring.

26'. in a loom having a lay and weft-inserting means, a support, a rock-shaft rotatably carried by said support and having a weft-engaging arm, said rock-shaft being angularly shiftable from a retracted position to an advanced position for tensioning the inserted Weft, a bushing rotatively adjustable in said support and forming a bearing for said rock-shaft, a coiled torsion spring surrounding said rockshaft and having one end engaging said bushing and the other end acting on said rock-shaft to swing said rock-shaft in Weft-tensioning direction, said bushing being angularly displaceable to vary the torsion of said spring, means for retaining said bushing in rotatively adjusted position, and means for swinging said rock-shaft to retracted position against the action of said spring, said support having a bore coaxial with said rockshaft and detachably and rotatively receiving said bushing therein, said bore having a diameter larger than that of said spring to permit passage of said spring over said rock-shaft for installing and replacing said spring.

21. in a loom having a lay and weft-inserting means, a support having a rock-shaft bearing, a rock-shaft rotatably carried by said support and having a weft-engaging arm, said rock-shaft being angularly shiftable from a retracted position to an advanced position for tensioning the inserted weft, a bearing member for said rock-shaft spaced axially from said support bearing and detachably carried by said support, a coiled torsion spring surrounding said rock-shaft beteen said support bearing and bearing member and acting on said rock-shaft to swing said rock-shaft in weft-tensioning direction, and means for swinging said rock-shaft to retracted position against the action of said spring, said bearing member being axially withdrawable from an end of said rock-shaft for replacing said spring.

22. In a loom having a shuttle movable back and forth between shuttle boxes, electric circuit means for controlling loom operation including alternately operable shuttlecontrolled switches at said shuttle boxes, each switch having a first closed position to which it is normally urged and having a second closed position to which it is shiftable by the boxed shuttle, said switches being connected in series in said circuit means and establishing circuit continuity therein when either of said switches is in its first closed position and the other switch is in its second closed position.

23. in a loom having a lay and means fo r inserting and tensioning a weft, loom control circuit means including first and second paths arranged in parallel and cooperatto maintain circuit continuity for permitting continued operation of the loom, means responsive to the presence of a normally tensioned weft for establishing said first circuit path, and cyclically operating switch means including a timer switch operable independently of the lay and opening said second circuit path for an interval during the period from the time scheduled for weft tensioning to the time scheduled for the end of the forward stroke of the lay, whereby it said first circuit path is open said loom control circuit means will be interrupted at said timer switch.

24. In a loom having a shuttle movable back and forth between shuttle boxes to lay a weft in a warp shed and further having means for beating up the weft, a pair of alternately actuated weft-tensioning members movable on advancing and retracting strokes and disposed at opposite sides of the warp shed, said members being alternately engageable with the laid weft on their advancing strokes to tension the weft before beat-up, actuating means for said weft-engaging members, and control means responslve to arrival of the shuttle at the respective shuttle boxes for effecting alternate actuation of said weft-engaging members on their advancing strokes immediately after boxing of the shuttle.

25. In a loom having a shuttle movable back and forth between shuttle boxes to lay a weft in the warp shed and having means for beating up the weft, a pair of alternately actuated reciprocably mounted weft-tensioning members engageable with the laid weft at opposite sides of the warp shed to tension the weft, and control means responsive to boxing of the shuttle for controlling alternate actuation of said weft-tensioning members.

26. In a loom having a lay and weft-inserting means, a weit-tensioning member movable on advancing and retracting strokes, an air cylinder operatively associated with said weft-tensioning member for moving said member on one of its strokes, valve means for controlling said air cylinder, and air-restricting means for regulating the rate of travel of said weft-tensioning member on both of its strokes.

References Cited in the file of this patent UNITED STATES PATENTS 978,248 Weissenborn Dec. 13, 1910 982,862 Peterson Jan. 31, 1911 1,602,615 lager Oct. 12, 1926 1,620,836 Schmiege Mar. 15, 1927 1,790,335 Weissenborn Jan. 27, 1931 2,089,620 Rossmann Aug. 10, 1937 2,377,800 Mascarenhas June 5, 1945 2,407,773 Fletcher Sept. 17, 1946 2,469,200 Matweeff May 3, 1949 2,477,996 Mascarenhas Aug. 2, 1949 2,499,887 Sullivan Mar. 7, 1950 2,600,667 Mason June 17, 1952 2,648,354 Mascarenhas Aug. 11, 1953 2,753,894 Looshin et a1. July 10, 1956 

